The show has been very careful not to reveal any information about Monroe's last name. This past episode, when Felix was searching for Monroe's number in his booklet, the camera only showed his number and not the name Felix had written down.

I think it has become one of those things about the show. Like an inside joke. Of all the characters, we know more about monroe and his family then any one else. Yet he is the only one we do not know the family name.

What follows is pure speculation on my part as to what would be a good surname for Monroe.

If they ever give him a last name perhaps it could be one that is a reference to Blutbad. For example it could be one with a meaning referring to Wolf/Dog/Hound since Blutbad are wolf-like Wesen (Wolf and all its variants might be a little too obvious, so here're some other options: Blevins, Connell, Cooney, Lowell, Stidolph), or even Forest (Forst, Holtzer, Holtzclaw, or even Grunwald which is a variant of Greenwalt, in reference to Grimm co-creator David Greenwalt). Finally, surnames like Blood or Hood (in reference to Red Riding Hood) might work, but would be a little obvious like Wolf/Wolff.

71.166.62.83 wrote:What follows is pure speculation on my part as to what would be a good surname for Monroe.

If they ever give him a last name perhaps it could be one that is a reference to Blutbad. For example it could be one with a meaning referring to Wolf/Dog/Hound since Blutbad are wolf-like Wesen (Wolf and all its variants might be a little too obvious, so here're some other options: Blevins, Connell, Cooney, Lowell, Stidolph), or even Forest (Forst, Holtzer, Holtzclaw, or even Grunwald which is a variant of Greenwalt, in reference to Grimm co-creator David Greenwalt). Finally, surnames like Blood or Hood (in reference to Red Riding Hood) might work, but would be a little obvious like Wolf/Wolff.

Holtzclaw might not be a good choice since it has "claw" in it and they're dealing with Black Claw at the moment. Holtzer would be a better choice, as it's a good sounding German name (and we know Monroe speaks fluent German and his ancestors were German, like Nick's).

Silas Weir Mitchell has spoken up about this several times in the years past, to quote the news article, after interviewing Mitchell

">Mitchell met with TV writers during a press call, noting that his character’s name is Monroe – just Monroe. “Somehow the name Eddie Monroe mistakenly got out there and now everyone assumes my character’s name is Eddie Monroe – for the record it’s just Monroe.”

In another interview the actor was asked about the nameafter the viewers finding out that Wu first name is Drew (honest.. drew wu.. they didnt think on that too hard haha)
Mitchell said .. Monroe is Monroe... or is it, If I knew, i wouldnt tell you, how good of a riddle is that one"